08-12-2019, 10:54 AM
Could not get a gasket off the shelf that didn't overlap 57mm bores so made up this. Have used solid copper in several engines with very mixed results so not a great fan. However this idea certainly holds the compression (7.5:1) with a David Dye head. There were some initial dribbles at the manifold side which have now settled down. The clamping pressure on the Austin head just isn't that great. It was a new block so went to 25lbs.
One thing that has become apparent is the lack of good quality head gaskets that can also accomodate larger overbores. I did some investigation and could get modern black Payen style gaskets made with compression and water rings in all the right places. The price was not that bad, retailing at arround £40, but it would need time spent on prototyping and testing which I don't have, and though I think the price would be OK for something that worked way better than existing I wonder if most folks would still just buy the cheaper existing ones.
One thing that has become apparent is the lack of good quality head gaskets that can also accomodate larger overbores. I did some investigation and could get modern black Payen style gaskets made with compression and water rings in all the right places. The price was not that bad, retailing at arround £40, but it would need time spent on prototyping and testing which I don't have, and though I think the price would be OK for something that worked way better than existing I wonder if most folks would still just buy the cheaper existing ones.